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πŸ”— Jacquard Machine

πŸ”— Textile Arts

The Jacquard machine (French:Β [Κ’akaʁ]) is a device fitted to a power loom that simplifies the process of manufacturing textiles with such complex patterns as brocade, damask and matelassΓ©. It was invented by Joseph Marie Jacquard in 1804, based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Baptiste Falcon (1728), and Jacques Vaucanson (1740). The machine was controlled by a "chain of cards"; a number of punched cards laced together into a continuous sequence. Multiple rows of holes were punched on each card, with one complete card corresponding to one row of the design. Several such paper cards, generally white in color, can be seen in the images below. Chains, like Bouchon's earlier use of paper tape, allowed sequences of any length to be constructed, not limited by the size of a card.

Both the Jacquard process and the necessary loom attachment are named after their inventor. This mechanism is probably one of the most important weaving inventions as Jacquard shedding made possible the automatic production of unlimited varieties of pattern weaving. The term "Jacquard" is not specific or limited to any particular loom, but rather refers to the added control mechanism that automates the patterning. The process can also be used for patterned knitwear and machine-knitted textiles, such as jerseys.

This use of replaceable punched cards to control a sequence of operations is considered an important step in the history of computing hardware.

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πŸ”— Spaghettification

πŸ”— Physics πŸ”— Physics/relativity

In astrophysics, spaghettification (sometimes referred to as the noodle effect) is the vertical stretching and horizontal compression of objects into long thin shapes (rather like spaghetti) in a very strong non-homogeneous gravitational field; it is caused by extreme tidal forces. In the most extreme cases, near black holes, the stretching is so powerful that no object can withstand it, no matter how strong its components. Within a small region the horizontal compression balances the vertical stretching so that small objects being spaghettified experience no net change in volume.

Stephen Hawking described the flight of a fictional astronaut who, passing within a black hole's event horizon, is "stretched like spaghetti" by the gravitational gradient (difference in strength) from head to toe. The reason this happens would be that the gravity force exerted by the singularity would be much stronger at one end of the body than the other. If one were to fall into a black hole feet first, the gravity at their feet would be much stronger than at their head, causing the person to be vertically stretched. Along with that, the right side of the body will be pulled to the left, and the left side of the body will be pulled to the right, horizontally compressing the person. However, the term "spaghettification" was established well before this. Spaghettification of a star was imaged for the first time in 2018 by researchers observing a pair of colliding galaxies approximately 150 million light-years from Earth.

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πŸ”— Von Neumann's Elephant

πŸ”— Mathematics

Von Neumann's elephant is a problem in recreational mathematics, consisting of constructing a planar curve in the shape of an elephant from only four fixed parameters. It originated from a discussion between physicists John von Neumann and Enrico Fermi.

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πŸ”— $100 Hamburger

πŸ”— Aviation πŸ”— Project-independent assessment

$100 hamburger ("hundred-dollar hamburger") is aviation slang for the excuse a general aviation pilot might use to fly.

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πŸ”— Defenestration

πŸ”— Death πŸ”— Glass

Defenestration (from Old French fenestre, inherited from Latin fenestra) is the act of throwing someone or something out of a window. The term was coined around the time of an incident in Prague Castle in the year 1618 which became the spark that started the Thirty Years' War. This was done in "good Bohemian style"; this referred to the defenestration which had occurred in Prague's City Hall almost 200 years earlier (July 1419), which also on that occasion led to war: the Hussite war. The word comes from the New Latin de- (down from) and fenestra (window or opening). Likewise, it can also refer to the condition of being thrown out of a window, as in "The Defenestration of Ermintrude Inch".

While the act of defenestration connotes the forcible or peremptory removal of an adversary, and the term is sometimes used in just that sense, it also suggests breaking the windows in the process (de- also means removal).

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πŸ”— Hacker's Delight

πŸ”— Computing πŸ”— Books

Hacker's Delight is a software algorithm book by Henry S. Warren, Jr. first published in 2002. It presents fast bit-level and low-level arithmetic algorithms for common tasks such as counting bits or improving speed of division by using multiplication.

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πŸ”— Angus Barbieri's fast

πŸ”— Biography πŸ”— Medicine πŸ”— Food and drink πŸ”— Scotland

Scottish man Angus Barbieri (1939 – 7 September 1990) fasted for 382 days, from June 1965 to July 1966. He lived on tea, coffee, soda water, and vitamins while living at home in Tayport, Scotland, and frequently visiting Maryfield Hospital for medical evaluation. He lost 276 pounds (125Β kg) and set a record for the length of a fast.

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πŸ”— London–Calcutta Bus Service

πŸ”— India πŸ”— Transport πŸ”— Travel and Tourism

The bus service from London, England to Calcutta, India (now Kolkata) was considered to be the longest bus route in the world. The bus service, which started in 1957, was routed to India via Belgium, Yugoslavia and North Western India. This route is also known as the Hippie Route. According to reports, it took about 50 days for the bus to reach Calcutta from London. The voyage was over 10,000 miles (16,000Β km) one way and 20,300 miles (32,700Β km) for the round trip. It was in service until 1976. The cost of the trip one-way was Β£85 in 1957 and Β£145 in 1973. This amount included food, travel and accommodation.

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πŸ”— Buridan's Ass

πŸ”— Philosophy πŸ”— Philosophy/Logic

Buridan's ass is an illustration of a paradox in philosophy in the conception of free will. It refers to a hypothetical situation wherein an ass that is equally hungry and thirsty is placed precisely midway between a stack of hay and a pail of water. Since the paradox assumes the ass will always go to whichever is closer, it dies of both hunger and thirst since it cannot make any rational decision between the hay and water. A common variant of the paradox substitutes two identical piles of hay for the hay and water; the ass, unable to choose between the two, dies of hunger.

The paradox is named after the 14th-century French philosopher Jean Buridan, whose philosophy of moral determinism it satirizes. Although the illustration is named after Buridan, philosophers have discussed the concept before him, notably Aristotle, who used the example of a man equally hungry and thirsty, and Al-Ghazali, who used a man faced with the choice of equally good dates.

A version of this situation appears as metastability in digital electronics, when a circuit must decide between two states based on an input that is in itself undefined (neither zero nor one). Metastability becomes a problem if the circuit spends more time than it should in this "undecided" state, which is usually set by the speed of the clock the system is using.

πŸ”— Wetware computer

πŸ”— Computing

A wetware computer is an organic computer (which can also be known as an artificial organic brain or a neurocomputer) composed of organic material such as living neurons. Wetware computers composed of neurons are different than conventional computers because they are thought to be capable in a way of "thinking for themselves", because of the dynamic nature of neurons. While wetware is still largely conceptual, there has been limited success with construction and prototyping, which has acted as a proof of the concept's realistic application to computing in the future. The most notable prototypes have stemmed from the research completed by biological engineer William Ditto during his time at the Georgia Institute of Technology. His work constructing a simple neurocomputer capable of basic addition from leech neurons in 1999 was a significant discovery for the concept. This research acted as a primary example driving interest in the creation of these artificially constructed, but still organic brains.

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